Here is a video perfectly displaying why it is dangerous to ride aero bars in a group of cyclists. This cyclist was riding on his aero bars when the rider in front of him had to brake suddenly.
Because his hands were nowhere near the brakes and he was in a panic, the cyclist grabbed the front brake. This caused his front wheel to lock, sending him over the handle bars and into the pavement.

he should have moved around the group and then applied the brakes (thats what you do in a team tt)... still it should have easily been prevented if he weren't in the bars coming to what looks like a junction

His front brake is on the right because he is in a country that drives on the left (like Australia or New Zealand, where I am) - our brakes are swapped from the US. Didn't anyone notice they are on the left side of the road? Of course, aeros when following a wheel are still bloody idiotic, no matter where you ride.